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Baptism of Fire / North Sea Tiger Cub

Baptism of Fire

Baptism of Fire – Chapter 27 Excerpt (Pages 1-12 of 88)

“Life is either a daring adventure or nothing at all” – Helen Keller.

My first offshore saturation dive lockout was on the British sector on the Teesside C.O.D. pipeline, diving from the DSV Seaway Harrier that had completed its work in the Ekofisk field and relocated. My first dive was a memorable and exciting experience. Not entirely sure of the procedures, I followed the other divers around the ship’s bowels during dive preparations. The first task was to find a hot water diving suit in the store that fitted my build. After trying on several, I found a slightly older, worn, neoprene suit with the proper length that gave room for my broad shoulders. I then wrote my name with a permanent marker on the diving suit and continued with other preparations.

The universally used standard KMB 18 band masks have a neoprene hood, not a neck dam assembly. On bell runs, divers one and two primarily use KMB 17 hats, not band masks. In contrast, diver three, the dedicated bellman, uses the KMB 18 as it can be donned fast in an emergency without help.

One of the things that needed doing was to adjust my KMB 17 hat’s neck dam cuff. The neck dam’s glass fibre lower part is formed like a horseshoe, and the upper part has a stiff metal outer ring with neoprene and a thin rubber inner sleeve liner. The glass fibre horseshoe is hinged at the rear, enabling it to be hinged down ninety degrees so the neoprene and rubber cuff sleeve can be pulled over the diver’s head and placed around his neck. The horseshoe is then hinged back up, and the whole assembly latches to the hat’s circumferential collar, which hinders water from entering the helmet. If you have long hair, you must tuck your ponytail above the neck dam’s rubber cuff. I had observed colleagues pulling their neck dam over a suitable-sized plastic bucket and leaving it overnight to stretch. I did not have a whole night but would leave it on the bucket for as long as possible while finishing my preparations.

After suffering from tight neck seals while diving in the Navy, I already understood the importance of a well-fitting neck dam. The Navy standard Viking drysuits utilise a simplified neck dam, a splitable flexible plastic ring and a stainless steel clip placed into the suit’s neck cuff. I also wore KMB 17 C Superlite hats when attending the saturation course on board the dive barge Buldra and during a few in-shore dives. If your neck dam is too tight, you feel strangled and have a sensation of your eyes popping out of their sockets; too loose, and it could let water through, flooding the hat.

During bell lockouts, up to seven hours would be spent in the water, not a mere hour or two as when diving surface supplied. In addition to having a thick neck, I had veins far out in my skin, which added to the pressure felt from the neck dam. Some divers cut the neck dam rubber to make them fit better, but this was not popular with the company as all diving equipment is expensive.

Some neck-dam rubber sleeves are fabricated with transversely ridged rubber that eases the cutting to size. Excessive cutting could make the neck dam useless to other divers later. There was also the chance that cutting would leave a nick or uneven surface that would cause rubbing and irritation and could cause immense suffering throughout a saturation if the friction generated a weeping open wound.

Worse case, an incision, like a paper cut, might tear the rubber material, potentially flooding the hat and terminating a lockout. Although the helmet had slight overpressure, water would still seep in when the diver bent over with a neck dam rubber seal that was not attentively and favourably adjusted.

One might wonder how much it matters if only a minor part of one’s collective equipment rig is not suitably adjusted. From my experience, it matters a lot. To a degree, every piece of diving equipment can have an effect, cause frustration, heighten the risk, and reduce efficiency.

The following examples have caused me issues, the adjustment and curvature and or length of the gas supply or reclaim hose, a sized or non-gripping hot-water hose suit Hansen quick connect fitting, the securing of a carabiner, a pneumo hose that is too short, the lack of or excess film of baby shampoo added to the hat’s inner face glass, lack of Vaseline applied to one’s neck before donning the neck dam, the type of undergarments worn, loose or damaged push clips that retain the hat liner correctly inside the helmet, the wrapping of the hat liner chin strap, the bungee or rubber strap between the harness D-ring and the pin at the back of the hat, an incorrectly adjusted harness (too tight and your balls are pinched, too loose your umbilical becomes skewed), worn out knife scabbard staps, rusted and sized personal tools, sharp edges that can lacerate your hands, incorrectly sized heavy duty rubber gloves and much more.

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The following paragraphs related to neck dams are based on reports, court documents and first-hand accounts recorded from 2011-2014.

During a saturation dive on 30 October 2011 to a depth of one hundred and forty-six metres on the UK Central Sector of the North Sea, diving from the Floating Production Vessel (FVP) Balmoral for the dive company Integrated Subsea Solutions (ISS), a thirty-three-year-old British diver named Russell Robinson was found floating lifeless under the diving bell. Before locking out of the bell, Russel informed his bell partners Paul Stone and Simon Bradly that he had a new neck dam with a non-modified constricted rubber cuff sleeve and said to his bell partners that he found breathing strenuous and challenging. Still, as it tragically turned out, he decided to lock out. Russell subsequently passed out during the latter stages of the dive. Was it due lack of oxygenated blood delivery to his brain? After being recovered into the bell, he did not respond to first aid CPR treatment.

A fatal accident inquiry was sanctioned in Aberdeen, Scotland, in June of 2014, Under the Fatal Accidents and Sudden Deaths Inquiry Act of 1976. The court participants were duly summoned to determine the causation of North Sea diver Russell Robinson’s untimely death.

Robinson was a healthy, young, fit father who died nearly one hundred and fifty metres underwater. He had complained that the equipment around his neck was too tight before embarking on this dive. The court heard evidence from Richard Martins, a health and safety inspector and diving specialist. Richards told Aberdeen Sheriff Court that his investigation into the thirty-three-year-old diver’s untimely death was in-depth and that he almost certainly found that the technical equipment was not at fault on that fateful day of 30 October 2011. He stated the evidence seemed to suggest Mr Robinson had suffered some unknown medical problem at a depth of more than one hundred and forty metres below the surface.

The court previously heard evidence from Paul Stone and Simon Bradley, Robinson’s dive colleagues on the date of the incident, who both stated Robinson complained that his neck dam was too tight. Stone said Robinson decided to continue using the neck dam for the short duration he would be in the sea during a routine lockout. Stone said divers often cut a piece away to allow more room if the neck seal rubber was too tight. However, Robinson had no time to carry out the alteration before the dive began.

During the inquiry hearings, Martins read out loud from a book of regulations provided to divers, “Never dive with a neck dam that is too tight. A neck dam which is too tight can cause a diver to pass out due to the pressure on the neck’s carotid artery. Such pressure could lead to severe injury or death.” Martins added that the Health and Safety Executive Office had re-issued warnings to divers about the potential effects of having a tight neck dam following the incident on the FPV Balmoral. He added, “We have taken steps on the lessons learned from this investigation and passed them on to the wider industry to improve divers’ safety focussing on divers’ recovery and recovery equipment.”

Dr Grieve, a specialist who performed the Robinson post-mortem examination, has experience examining divers who have died during diving operations. His findings are not in any way disputed. Grieve gave the cause of death as “Death while diving (Saturation)”. He could not identify the fatal cause or the factors contributing to the deadly causation.

Having had the opportunity to consider the reports of the other experts involved in preparing reports for this inquiry and discussing their views with some of them, Grieve was able to set out the contending theories which had been put forward as to the physical cause of death. Grieve explained that no definitive cause of death could be proved by any of the consulted experts who had submitted reports. However, there was a degree of concordance amongst the experts regarding possible causes. Each expert had an opinion and something to support it, but each expert had a favoured view.

  1.  A sudden cardiac event was postulated as a cause of death. Dr Grieve could not exclude it but found nothing on the autopsy to show damage to the heart. Nor was there a genetic predisposition to such an event in Mr Robinson. He had no history of cardiac symptoms. There was no persuasive support for this cause among the experts.
  2.  Asthma and diabetes were each postulated. Although Mr Robinson appeared from his records to have a history of asthma in his younger years, Dr Grieve found no physical signs of damage to the respiratory system, such as would be expected if asthma had caused or contributed to the death. Diabetes had been raised because of past weight gain, and some signs were noticed by Mr Bradley when Mr Robinson’s helmet was removed. Dr Grieve and others discounted these, and the symptoms noted by Mr Bradley were explained as having other causes unrelated to diabetes.
  3.  The experts discussed bronchospasm and a lack of breathable gases reaching the alveoli in the deep lung area. These would both cause anoxic anoxia (no oxygen reaching the brain). Bronchospasm could not be confirmed or excluded because the tissues which would have been in spasm would have relaxed on death. Lack of breathable gas reaching the deep regions of the lung could not be confirmed on autopsy nor by other evidence, although it may fit with some of the signs of asphyxia found by Dr Grieve.
  4.  Dr Grieve did find signs of asphyxia. There was congestion of the face, cyanosis of the face and neck and petechial haemorrhaging. According to Dr Grieve, there are many potential causes of asphyxia, ranging from smothering through the crushing of the chest that would stop inhalation to the lack of breathable atmosphere to external compression. All of these will give rise to a lack of oxygen to the brain and, ultimately, death.
  5.  Dr Grieve had a concern over the tightness of Robinson’s neck dam. But could not be satisfied, in light of the fact that Robinson had no difficulties during the bulk of the dive and although there was some superficial bruising around Mr Robinson’s neck, it was neither deep nor extensive, that it had exerted sufficient pressure on Robinson’s neck to cause anoxic anoxia. Professor Busuttil discounted the bruising as inconsequential.
  6.  Dr Grieve hypothesised that when Robinson used the free flow system in his helmet to increase the gas flow available to him, that could have increased the external pressure on the neck dam, tightening further on the neck. However, the evidence suggested that Robinson was having difficulty breathing before the free flow valve was opened. Thus, it could not have caused the original problem. Further, it has to be unlikely that a system designed to make it easier for the diver to breathe by reducing the need for active inspiration would be designed in such a way that it would increase the pressure on the diver’s neck and throat.
  7.  Thus, the expert evidence which postulated possible causes of death was not without difficulty. All of the suggested causes were based, to a greater or lesser extent, on speculation. None explained all of the circumstances observed, and none fitted all the facts as established by the evidence of events and of the findings on post-mortem examination.

During the closing statements, Sheriff Annella M. Cowan, Advocate, stated, “Mr Robinson’s fellow divers and his offshore colleagues, clearly, men of great physical and mental courage undertaking work in a hostile, alien environment, spoke indeed graphically about their job as saturation divers and about the situation they faced when their colleague Robinson became distressed towards the end of the dive. Their evidence was of great assistance to me in explaining not only the precautions which have to be taken and which were taken on this occasion in preparing for a saturation dive. But also the necessarily confined space in which Stone and Bradley had to work to bring the lifeless Robinson back into the bell.”

Court’s Finding: “Thus, the expert evidence which postulated possible causes of death was not without difficulty. All of the suggested causes were based, to a greater or lesser extent, on speculation. None explained all of the circumstances observed, and none fit all the facts as established by the evidence of events and the findings during post-mortem examination. Accordingly, I find as follows: Russell Richard Robinson, born 18 September 1978, died on 30 October 2011 at 18:37:35 while in the course of a diving operation being carried out from the Balmoral Floating Production Vessel at position Latitude 058 degrees, 13 minutes, 45.7 seconds north, Longitude 001 degree, 6 minutes, 31.22 seconds east in the Scottish area of the North Sea. The court’s statement following the fatal accident inquiry held in Aberdeen, Scotland, in June 2014 is: Mr Robinson died during saturation diving while locked out of the bell. No more specific cause of death can be ascertained.”

A further fatality occurred in the German sector on 03 May 2012. Stephen O’Malley from Liverpool, UK, aged forty-eight, died of neck dam hypoxic induced cardiac arrest when surface-supplied shallow air diving from the MV Blue Capalla at the Alpha Ventus wind farm. He reported prior to the dive that his neck dam was very tight. There was no dive basket, so the standby rescue diver took a long time to recover Stephan’s lifeless body. The initial medical report stated a heart attack; the British crown court opened an inquest in 2016 to further determine the causation of his death.

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Satisfied that I had found the best fit of the equipment available, I entered the decompression chamber with two other divers and their equipment, personal clothes, and toiletries. Divers call the pressure chambers “the bin”. We were then blown down to sixty-six metres, eight metres above seabed depth.

The term “blown down” means bringing the divers down to the required equivalent pressure of the planned living depth, typically approximately ten metres shallower than the actual working depth. If a decompression chamber is vacant, it would primarily be chosen for the blowdown. If occupied, divers can be blown down to depth in any other empty surfaced living chambers, the wet pots (TUPs), or in a bell. Then follows a six-hour hold at living depth to give them time to settle in and let their body’s tissue become saturated with gas equal to the surrounding ambient pressure.

Once at depth, we moved our gear from the decompression chamber into the dedicated living chamber. I selected a top bunk as a customary courtesy for the older divers, allowing them to sleep in the lower bunk. Then preparations for our sat’s first bell run started.

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The dive tables used to decompress saturation divers are based empirically on the diver’s body tissues and blood becoming saturated with gases after six to eight hours, depending on the gas mixtures utilised and the ambient temperature. However, in reality, the body’s various tissues are not wholly saturated before twelve hours or more have elapsed at that particular depth. Fatty tissue takes longer to both be saturated and to release dissolved gas. Unfit, fat, obese people are not ideal sat divers for this and numerous other logical, relevant reasons.

The saturation point is defined as when the body cannot absorb more dissolved gas at a given pressure. For example, hypothetically, if identical twins were blown down to the same depth. One twin finishes his job in five hours and fifty-five minutes, then immediately starts upon his decompression. The other twin spent ten minutes longer at depth, i.e. six hours and five minutes. The brothers would use entirely different decompression tables, where the first twin would reach surface pressure much faster than the second. For the other twin, his decompression time will be the same regardless of whether his decompression started directly after six hours and five minutes or alternatively started his decompression after remaining at that depth for two or six weeks.

Bounce diving was a standard method used during earlier days of deeper dives in the North Sea. It is still in use in some parts of the world, albeit not often used by the oil and gas industry due to inherent higher risks and short bottom times. For this type of dive, the divers enter an unpressurised bell. The bell’s outer trunking door is closed and sealed. The bell with surface atmospheric pressure descends to the planned working depth or the seabed. The “blowdown” is then performed at depth, equalising the pressure inside the bell to mirror the bell’s sea depth pressure. The divers then open the bell’s outer hatch and immediately start working. Every second counts, as time is not on their side. Upon exiting the bell, they must complete their work as rapidly as possible to avoid a prolonged decompression. After completing the job, the diver or divers re-enter the bell and seal the bell’s inner trunking door.

Companies have independent decompression tables with considerable variations. Some entirely decompressed while remaining inside the bell. Or, preferably, they would be brought to the surface in the sealed bell, starting decompression during the ascent while breathing the bottom gas mix up to a set depth. The bell would be mated to a TUP (wet pot) interconnected to a living chamber, and they would crawl through the pressurised trunking into the deck chamber to continue their decompression.

Others would decompress further and even change the breathing gas mixture during the ascent in the bell using BIBS (built in breathing system) masks. After the bell was mated and equalised with the TUP, their decompression would be concluded inside the deck chamber.

The two latter-mentioned preferred options allowed most of the decompression to be done in a warm, dry chamber. All the methods gradually allowed the divers to return to surface pressure, changing the breathing gas mix to an intermediate mix before the final stages using pure oxygen via BIBS. Without the availability of pure oxygen during the final stages, the decompression would take much longer. These two latter options, if required, enabled the next dive team to conduct a back-to-back bounce dive after the divers had vacated the bell and transferred to an interconnected chamber to continue their decompression. The bell could then be surfaced. However, the second team would carry a higher risk of hypothermia as they could not vacate the bell and enter the warm chamber while the chamber was still occupied by divers decompressing at a shallower depth. However, if the system had two living/decompression chambers interconnected to the TUP, this clash would not occur.

On some earlier bounce diving sites, if decompression was performed while in the bell, hot water was sprayed on the bell’s external surface to alleviate the terrible cold the divers suffered. In addition, if a situation arose where the divers in the bell had to be recovered into the chamber rapidly, the decompressing divers inside that chamber would have to be recompressed quickly to the depth of the bell atmosphere. In addition, with a small bell bounce dive team, if four men simultaneously were pressurised, it would impact the emergency response effort. The team would have to be substantially larger to safely conduct back-to-back bounce diving.

Bounce diving was primarily utilised for deeper diving during a transition period before saturation diving became widespread, thus avoiding having divers decompressing in cold, inhospitable, rough seas. Graham Mann recalls the mind-numbing painful cold of surface-orientated gas diving to eighty metres depths, along with a brief “hit” of nitrogen narcosis that arises when changing back to breathing air at eighteen metres depth during the in-wate The dive tables used to decompress saturation divers are based empirically on the diver’s body tissues and blood becoming saturated with gases after six to eight hours, depending on the gas mixtures utilised and the ambient temperature. However, in reality, the body’s various tissues are not wholly saturated before twelve hours or more have elapsed at that particular depth. Fatty tissue takes longer to both be saturated and to release dissolved gas. Unfit, fat, obese people are not ideal sat divers for this and numerous other logical, relevant reasons.

The saturation point is defined as when the body cannot absorb more dissolved gas at a given pressure. For example, hypothetically, if identical twins were blown down to the same depth. One twin finishes his job in five hours and fifty-five minutes, then immediately starts upon his decompression. The other twin spent ten minutes longer at depth, i.e. six hours and five minutes. The brothers would use entirely different decompression tables, where the first twin would reach surface pressure much faster than the second. For the other twin, his decompression time will be the same regardless of whether his decompression started directly after six hours and five minutes or started his decompression after remaining at that depth for two or six weeks.

Bounce diving was a standard method used during earlier days of deeper dives in the North Sea. It is still in use in some parts of the world, albeit not often used by the oil and gas industry due to inherent higher risks and short bottom times. For this type of dive, the divers enter an unpressurised bell. The bell’s outer trunking door is closed and sealed. The bell with surface atmospheric pressure descends to the planned working depth or the seabed. The “blowdown” is then performed at depth, equalising the pressure inside the bell to mirror the bell’s sea depth pressure. The divers then open the bell’s outer hatch and immediately start working. Every second counts, as time is not on their side. Upon exiting the bell, they must complete their work as rapidly as possible to avoid a prolonged decompression. After completing the job, the diver or divers re-enter the bell and seal the bell’s inner trunking door.

Companies have independent decompression tables with considerable variations. Some entirely decompressed while remaining inside the bell. Or, preferably, they would be brought to the surface in the sealed bell, starting decompression during the ascent while breathing the bottom gas mix up to a set depth. The bell would be mated to a TUP (wet pot) interconnected to a living chamber, and they would crawl through the pressurised trunking into the deck chamber to continue their decompression.

Others would decompress further and even change the breathing gas mixture during the ascent in the bell using BIBS (built in breathing system) masks. After the bell was mated and equalised with the TUP, their decompression would be concluded inside the deck chamber.

The two latter-mentioned preferred options allowed most of the decompression in a warm, dry chamber. All the methods gradually allowed the divers to return to surface pressure, changing the breathing gas mix to an intermediate mix before the final stages using pure oxygen via BIBS. Without the availability of pure oxygen during the final stages, the decompression would take much longer. These two latter options, if required, enabled the next dive team to conduct a back-to-back bounce dive after the divers had vacated the bell and transferred to an interconnected chamber to continue their decompression. The bell could then be surfaced. However, the second team would carry a higher risk of hypothermia as they could not vacate the bell and enter the warm chamber while the chamber was still occupied by divers decompressing at a shallower depth. However, if the system had two living/decompression chambers interconnected to the TUP, this clash would not occur.

On some earlier bounce diving sites, if decompression was performed while in the bell, hot water was sprayed on the bell’s external surface to alleviate the terrible cold the divers suffered. In addition, if a situation arose where the divers in the bell had to be recovered into the chamber rapidly, the decompressing divers inside that chamber would have to be recompressed quickly to the depth of the bell atmosphere. In addition, with a small bell bounce dive team, if four men simultaneously were pressurised, it would impact the emergency response effort. The team must be substantially larger to safely conduct back-to-back bounce diving.

Bounce diving was primarily utilised for deeper diving during a transition period before saturation diving became widespread, thus avoiding having divers decompressing in cold, inhospitable, rough seas. Graham Mann recalls the mind-numbing painful cold of surface-orientated gas diving to eighty metres depths, along with a brief “hit” of nitrogen narcosis that arises when changing back to breathing air at eighteen metres depth during the in-water decompression. These two sensory experiences have to be physically experienced to be appreciated.

For clarity, there are five basic types of deeper diving using helium or tri-mix gas mixtures. No closed bells are required for the first three methods mentioned below.

The first method is military or sports diving using rebreathers with in-water decompression. Commercial divers avoid this method for numerous good reasons.

The divers descend from the surface/platform/vessel with their umbilicals delivering the correct gas mixtures with the second method. When they finish working, their decompression is similar to that of scuba divers. They must make several stops in the water at set levels as they ascend. Decompression can take hours, and the divers are affected by the elements, current, swell, and waves. Cold and discomfort are their companions. If any medical issues should arise, their options for treatment are minimal. This method carries the highest risk.

The third method is similar to the first, albeit the divers decompress in the water up to the nine-metre depth stop. They then are ushered as fast as possible up to the surface, crawl into a chamber, immediately recompressed to twelve metres of depth in less than five minutes, and then decompress from there while breathing oxygen in intervals. Regardless, their bottom time is limited to avoid getting decompression sickness. Therefore, these two methods are rarely used in modern deeper diving.

The fourth technique is the bounce diving explained above.

The fifth and last method is regular saturation diving, where divers are pressurised, saturated with the correct gas mixtures, and kept saturated inside the pressure chamber. Daily descending and ascending to and from the work site in an enclosed diving bell, weather permitting, for as many days as the job requires or as long as enforced regulations allow. Then they are decompressed within the chambers. To my knowledge, the longest decompression from a saturation ever performed took twenty-four days. r decompression. These two sensory experiences have to be physically experienced to be appreciated.

For clarity, there are five basic types of deeper diving using helium or tri-mix gas mixtures. No closed bells are required for the first three methods mentioned below.

The first method is military or sports diving using rebreathers with in-water decompression. Commercial divers avoid this method for numerous good reasons.

The divers descend from the surface/platform/vessel with their umbilicals delivering the correct gas mixtures with the second method. When they finish working, their decompression is similar to that of scuba divers. They must make several stops in the water at set levels as they ascend. Decompression can take hours, and the divers are affected by the elements, current, swell, and waves. Cold and discomfort are their companions. If any medical issues should arise, their options for treatment are minimal. This method carries the highest risk.

The third method is similar to the first, albeit the divers decompress in the water up to the nine-metre depth stop. They then are ushered as fast as possible up to the surface, crawl into a chamber, immediately recompressed to twelve metres of depth in less than five minutes, and then decompress from there while breathing oxygen in intervals. Regardless, their bottom time is limited to avoid getting decompression sickness. Therefore, these two methods are rarely used in modern deeper diving.

The fourth technique is the bounce diving explained above.

The fifth and last method is regular saturation diving, where divers are pressurised, saturated with the correct gas mixtures, and kept saturated inside the pressure chamber. Daily descending and ascending to and from the work site in an enclosed diving bell, weather permitting, for as many days as the job requires or as long as enforced regulations allow. Then they are decompressed within the chambers. To my knowledge, the longest decompression from a saturation ever performed took twenty-four days.

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I was designated to be diver one on my first operational offshore sat bell run and asked the bellman if I could follow him up into the bell to perform extended pre-dive internal bell checks. Both the bellman and the dive supervisor were pleased by my eager initiative. This request was to familiarise myself further with the system. During the month already spent on board, each day after my twelve-thirteen hour air dive shifts had ended, I would inspect and study the outside of the system’s two bells and the other associated interconnected parts of the onboard diving system. I also assimilated information from numerous binders and folders detailing the company’s procedures. I familiarised myself with the internal delineated schematics of Seaway Harrier’s bells insofar as I could not gain access due to them both being constantly pressurised. Before each dive, the diver assigned bellman duties include spending an hour or two preparing equipment in the wet pot/TUP and conducting the necessary pre-dive bell checks.

The following thirty minutes were hectically spent with the bellman inside the bell performing a complete internal checklist while continuously communicating with dive control. The checklist index is similar to a pre-flight cockpit check in an aeroplane. However, inside an aeroplane cockpit, verification is between the pilots and a little with the flight tower. Inside the bell, the checks are performed in close collaboration between the designated bellman and the dive supervisor in dive control via a headset. Every valve position is systematically and sequentially cross-checked and registered. Depending on the bell, up to or over ninety individual valve positions must be confirmed in the correct position. All operational valves are function tested, including the gas supply to the dive hats. Numerous pressure gauge readings are verified, ensuring the pressures shown are inside the given parameters. Communication, microphones, speakers and through-water coms are also verifiably proven functional. All equipment, tooling, rescue and survival gear, and spares are closely inventoried and inspected, in itself a demanding task as there can be well over thirty critical items. The camera feeds, sampling and monitoring equipment are also function tested.

The development from the elementary first generation of diving bells into today’s modern diving bells is astounding, similar to the differences between a WWI biplane and a modern-day Jet plane. The divers rotate being the bellman, so it is your turn every third day in a three-person team while the other two men are outside the bell working. All the valves inside and outside the bell are essential for the diver’s well-being and survival. There is no room for mistakes in this environment. Meticulous external bell checks are performed on the bell’s outside valve penetrators and equipment by the designated deck diver before and after each bell run. Overall, and understandably, the internal bell check was performed profoundly, meticulously, comprehensively and elaborately. Three men’s lives were at stake, not to mention other divers’ lives if, God forbid, a rescue mission should arise due to equipment failure. All diving bells are set up, laid out and configured somewhat differently. Even two identical bells on the same vessel are different. The configuration depends on how old they are and how much they have been modified and improved. Therefore, my newly gained knowledge would not automatically apply to diving in another vessel’s bell.

One intricate valve assembly block inside the diving bell and multiple associated valve assemblies on board the dive vessel control the delivery and recycling of the gas the divers breathe. This system is named the gas reclaim (Gasmizer Helium). The gas mixture that arrives from the ship’s massive gas banks travels down through a hose in the bell’s main umbilical, then from the bell’s distribution manifold via the individual umbilicals out to the diver’s helmets and by an ingenious Superflow/Ultraflow demand valve delivers breathing gas. When the diver breathes out, the expelled gas is routed by British inventor Alex Copson’s Helinaut valve back to the bell via the umbilical’s reclaim return hose, then back up the main umbilical via a dedicated hose via manifolds on the ship to the gas bag, scrubbers and recompression pumps (gas treatment plant cleaning and recycling system). Thus, only a minimal volume of super-expensive helium gas is expelled from the helmet’s closed circuit and wasted. The gas reclaim system is complicated, so the bellman rarely touches the valves associated with this sensitive, circular system. The rule of thumb is, “If it works, do not touch it; leave it alone.”

The initial gas reclaim prototypes tested in the mid-seventies were not without dangers. A fatality occurred on 28 August 1973 on board one of the world’s largest derrick lay barges, the L. B. Meaders owned by American Brown & Root Inc, while it was operating on Block 10 in the UKCS of the North Sea. The Taylor Diving & Salvage Company were conducting saturation bell diving from the barge at a depth of ninety-seven metres using a first-generation gas reclamation system. Twenty-nine-year-old lead diver American Paul J. Havlena, accompanied by his twenty-eight-year-old bell partner Helvey, who was also American, were at depth during the nighttime. Paul was performing non-routine maintenance work on a pipeline. Paul was locked out of the bell while Helvey was tendering him inside the bell.

The dive supervisor requested Paul return to the bell as his shift ended. Paul, however, requested permission to complete the ongoing job and received permission to continue for another fifteen minutes. One minute after that verbal exchange, Paul stated that he was returning to the bell but did not elaborate or explain why he had changed his mind. He then asked for help from Helvey, who immediately exited the bell. To Helvey’s dire apprehension, he found Paul lifeless upside down beneath the bell’s suspended clump weight. Paul’s hat gas delivery valve appeared to be shut, and it is reported that Helvey thought he opened it. Helvey struggled to get Paul back into the bell. A standby diver was deployed from the surface. Together, they managed to manhandle Paul back into the bell, where resuscitation attempts were performed, sadly to no avail. Paul was confirmed dead in the bell.

The autopsy listed the cause of Paul’s death as pulmonary barotrauma resulting in pneumothorax. Commander Jackie Warner states in his book, “Requiem For A Diver” published in 1990, “There is little doubt that the accident was caused by inadequate equipment design.” This death caused a setback of several years in achieving a total helium reclamation goal set by the oil field operating diving companies. (Developing and implementing a reliable, safe, efficient, robust reclaim system would take an additional seven years)……………..


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